Cash flow problems can kill businesses that might otherwise survive. According to a U.S. Bank study, 82 percent of business failures are due to poor cash management. To prevent this from happening to your business, here are my 10 cash flow rules to remember.

Profits aren't cash; they're accounting. And accounting is a lot more creative than you think. You can't pay bills with profits. Actually profits can lull you to sleep. If you pay your bills and your customers don't, it's suddenly business hell. You can make profits without making any money.

Cash flow isn't intuitive. Don't try to do it in your head. Making the sales doesn't necessarily mean you have the money. Incurring the expense doesn't necessarily mean you paid for it already. Inventory is usually bought and paid for and then stored until it becomes cost of sales.

Growth sucks up cash. It's paradoxical. The best of times can be hiding the worst of times. One of the toughest years my company had was when we doubled sales and almost went broke. We were building things two months in advance and getting the money from sales six months late. Add growth to that and it can be like a Trojan horse, hiding a problem inside a solution. Yes, of course you want to grow; we all want to grow our businesses. But be careful because growth costs cash. It's a matter of working capital. The faster you grow, the more financing you need.

Business-to-business sales suck up your cash. The simple view is that sales mean money, but when you're a business selling to another business, it's rarely that simple. You deliver the goods or services along with an invoice, and they pay the invoice later. Usually that's months later. And businesses are good customers, so you can't just throw them into collections because then they'll never buy from you again. So you wait. When you sell something to a distributor that sells it to a retailer, you typically get the money four or five months later if you're lucky.

Inventory sucks up cash. You have to buy your product or build it before you can sell it. Even if you put the product on your shelves and wait to sell it, your suppliers expect to get paid. Here's a simple rule of thumb: Every dollar you have in inventory is a dollar you don't have in cash.

Working capital is your best survival skill. Technically, working capital is an accounting term for what's left over when you subtract current liabilities from current assets. Practically, it's money in the bank that you use to pay your running costs and expenses and buy inventory while waiting to get paid by your business customers.

"Receivables" is a four-letter word. (See rule 4.) The money your customers owe you is called "accounts receivable." Here's a shortcut to cash planning: Every dollar in accounts receivable is a dollar less cash.

Bankers hate surprises. Plan ahead. You get no extra points for spontaneity when dealing with banks. If you see a growth spurt coming, a new product opportunity or a problem with customers paying, the sooner you get to the bank armed with charts and a realistic plan, the better off you'll be.

Watch these three vital metrics: "Collection days" is a measure of how long you wait to get paid. "Inventory turnover" is a measure of how long your inventory sits on your working capital and clogs your cash flow. "Payment days" is how long you wait to pay your vendors. Always monitor these three vital signs of cash flow. Project them 12 months ahead and compare your plan to what actually happens.

If you're the exception rather than the rule, hooray for you. If all your customers pay you immediately when they buy from you, and you don't buy things before you sell them, then relax. But if you sell to businesses, keep in mind that they usually don't pay immediately.